Multiple Injections of Autologous Adipose-Derived Stem Cells Accelerate the Burn Wound Healing Process and Promote Blood Vessel Regeneration in a Rat Model

Stem cell-based therapies have the potential to heal burn wounds, but thus far have had limited success in clinical practice. This study aimed to test and improve the therapeutic effects of adipose-derived stem cells (ASCs) on burn wound healing in a rat model. We also explored the role of ASCs in burn wound healing We first isolated the autologous ASCs of each Sprague-Dawley rat used in this experiment and expanded them in vitro. Then, a 2-cm² burn wound was made on the dorsal skin of each rat using a specialized heating iron. The treated rats received either one or three injections of 2 × 10⁶ green fluorescent protein-labeled autologous ASCs, and the control rats received injections of the same volume of phosphate-buffered saline. A digital camera was employed to capture images of the wound area. We explored the role of ASCs in burn wound healing by cell tracing, evaluation of blood vessel number, analysis of a rat cytokine array panel, and cell proliferation in vivo. Multiple injections of autologous ASCs accelerated the wound healing process more efficiently compared with that observed in the control treatment. A rat cytokine array test showed that transplanting ASCs led to significantly elevated expression of VEGF. Therefore, angiogenesis was significantly improved in ASC-treated rats, as more microvessels were observed in the wound skin of the experimental rats than in that of the control rats. Transplanted ASCs not only survived in the wound bed but also participated in the blood vessel regeneration process. ASCs also accelerated the wound healing process by increasing the rate of cell proliferation in the wound skin. Our data suggest that autologous ASCs transplantation accelerated the burn wound healing process and promoted blood vessel regeneration. ASCs could potentially be used in burn wound healing treatment.